Abstract: The Linxia Basin is situated in the southeastern part of Gansu Province , China , and it is a flexural basin bounded by the Leijishan fault , North Qinling fault , and the Maxian mountain (Fang et al. , 2003) . The Cenozoic strata are very thick and well-exposed in the Linxia Basin , and abundant mammal fossils are discovered from the strata (Fig. 1) . Before the 1950s , there were few works done about the Tertiary strata in the Linxia Basin , and the sediments were mostly referred to the informal name“Gansu Group”. Subsequently, the Tertiary red beds in the Linxia Basin were given the formal name Linxia Formation , the age being determined to be Pliocene , and was divided into four lithologic members ( GRGIT , 1965) . Qiu et al. (1990,1991) first described the Early and Late Miocene fossils in the Linxia Basin. After comparing the Jiaozigou section with the stratotype of the Linxia Fm., Qiu et al. (1990) and Xie (1991) suggested that the Linxia Fm. limited to the fourth member of the original Linxia Fm. , with an age of Late Miocene. Li et al. (1995) further divided the Linxia strata , and renamed different formations from the Late Oligocene to the Holocene. We adopt some of their divisions and revised others, and we recognized the following sequences (from lower to upper) : ? Early Oligocene Tala Formation, Late Oligocene Jiaozigou Formation, Middle Miocene Dongxiang and Laogou Formations, Late Miocene Liushu Formation, Early Pliocene Hewangjia Formation, Late Pliocene Jishi Formation, and Early Pleistocene Wucheng Loess (Fig. 2 ; Table 1) .